I've had a very slow leak, no noticeable oil consumption, just an occasional smoke puff from oil hitting the exhaust from time to time. Oil appears around the edges of the valve cover.

Today, I took off the engine cover to investigate a little closer and noticed some reflection around the sparkplug to the right of the valvetronic motor. Pulled the coil from that plug and the one next to it. There appears to be oil around the sparkplug on the immediate right of the valvetronic, but not on the plug to the right of the "oily plug" (see pic).

So, I'm wondering... is this a for sure sign of vcg leak? Could it be anything worse? or could there be any chance it's oil filter housing? I've found some grime around the oil filter housing but no obvious trail or oil seeping.

Yes! Valve cover gasket goes around the top of the head, but then there are a set of two gaskets for the holes for the spark plugs - basically when you buy a valve cover gasket kit it includes these two other gaskets.

Very important to replace this sooner rather than later - the oil will eventually (if is not already too late) damage the swimming coil packs.

Yes! Valve cover gasket goes around the top of the head, but then there are a set of two gaskets for the holes for the spark plugs - basically when you buy a valve cover gasket kit it includes these two other gaskets.

Very important to replace this sooner rather than later - the oil will eventually (if is not already too late) damage the swimming coil packs.

dumb question: if I decide to attempt a DIY here, should I somehow soak up this oil before removing spark plugs?

dumb question: if I decide to attempt a DIY here, should I somehow soak up this oil before removing spark plugs?

Why do you want to take the spark plugs out? To replace with new?

I would definitely soak up and clean this excess oil off before taking the spark plugs out, in fact even when "clean" looking one should consider that there might be some not so easy to see grit and dust that you don't want finding its way into the combustion chamber.

But otherwise, the spark plugs don't need to come out when replacing the valve cover gasket, and in that case, once the valve cover is off it would then be easier to access and clean around the spark plugs.

Just an observation, it seems as though this is a more tricky job with the N52 than for instance the M54 - more cramped with the N52 and things like the strut brace will probably be in the way...

dumb question: if I decide to attempt a DIY here, should I somehow soak up this oil before removing spark plugs?

Why do you want to take the spark plugs out? To replace with new?

I would definitely soak up and clean this excess oil off before taking the spark plugs out, in fact even when "clean" looking one should consider that there might be some not so easy to see grit and dust that you don't want finding its way into the combustion chamber.

But otherwise, the spark plugs don't need to come out when replacing the valve cover gasket, and in that case, once the valve cover is off it would then be easier to access and clean around the spark plugs.

Just an observation, it seems as though this is a more tricky job with the N52 than for instance the M54 - more cramped with the N52 and things like the strut brace will probably be in the way...

But definitely still a DIY job!

thx for comments. Guess I assumed plugs needed to come out. I've seen pics where folks pull the metal sleeve around the plug, thought the plug was gone.

Everything I'm about to say, I mean with utmost respect...honestly, I do.

Based on the questions your asking, I do not recommend a DIY here. The E90 VCG change is a totally different animal than prior year models. I am a fairly good DIY'r with a descent tool collection, and failed at this one.

I had several complications. First, the reason your VCG is leaking is almost certainly because you have broken head cover bolts (super common with this engine). Depending on where they are broken off, this can get tricky. Second, when you remove the cover, I would give 10:1 odds that you break the oil separator hose that connects to the cover. Without proper tools, this can be challenging to replace. Third, once you get the cover off, putting it back on requires an angular torque wrench to properly secure it. You will need a digital wrench here, as you will not have enough room to get in to the aft bolts with a angular dial.

This job on this particular model is not for the faint at heart. It is labor intensive and time consuming..and requires a bit more than basic tools and skills. I'm gathering from the questions you asked (ie removing the spark plugs) your aren't equipped for this.

My friendly, humble advice (from someone who tried and failed here) is to find a local BMW Indy shop and just pay then to do it. My local shop quoted $400 including parts....WELL worth it.

Yeah I agree with post above. Thats the reason I m waiting to replace mine. This job requieres experience. I have a very slow VCG leak, My oil level has not moved in almost 5months. I will ask my friend whos a BMW tech and see how much he charges me for the VCG replacement. For now I need to change my spark plugs since they will be due at 100k miles. I wonder If I should do spark plugs and VCG at the same time. Anyone?
Cheers!

Everything I'm about to say, I mean with utmost respect...honestly, I do.

Based on the questions your asking, I do not recommend a DIY here. The E90 VCG change is a totally different animal than prior year models. I am a fairly good DIY'r with a descent tool collection, and failed at this one.

I had several complications. First, the reason your VCG is leaking is almost certainly because you have broken head cover bolts (super common with this engine). Depending on where they are broken off, this can get tricky. Second, when you remove the cover, I would give 10:1 odds that you break the oil separator hose that connects to the cover. Without proper tools, this can be challenging to replace. Third, once you get the cover off, putting it back on requires an angular torque wrench to properly secure it. You will need a digital wrench here, as you will not have enough room to get in to the aft bolts with a angular dial.

This job on this particular model is not for the faint at heart. It is labor intensive and time consuming..and requires a bit more than basic tools and skills. I'm gathering from the questions you asked (ie removing the spark plugs) your aren't equipped for this.

My friendly, humble advice (from someone who tried and failed here) is to find a local BMW Indy shop and just pay then to do it. My local shop quoted $400 including parts....WELL worth it.

Thanks for your reply and info! I have noticed that the general appearance of the valve cover and what little can be seen of the valve cover gasket is markedly different to the M54 engines. So what you said does make sense. Plus one thing I have noticed is that the engine is a bit more cramped to work on compared to the M54.

Didn't know about the other technicalities and good to know!

From what I have on my car's motorplan history, the valve cover gasket was replaced just before I bought the car, and so far it is still bone dry and spotless everywhere that I can see, so clearly was properly replaced! And hopefully won't need replacement any time soon!

Everything I'm about to say, I mean with utmost respect...honestly, I do.

Based on the questions your asking, I do not recommend a DIY here. The E90 VCG change is a totally different animal than prior year models. I am a fairly good DIY'r with a descent tool collection, and failed at this one.

I had several complications. First, the reason your VCG is leaking is almost certainly because you have broken head cover bolts (super common with this engine). Depending on where they are broken off, this can get tricky. Second, when you remove the cover, I would give 10:1 odds that you break the oil separator hose that connects to the cover. Without proper tools, this can be challenging to replace. Third, once you get the cover off, putting it back on requires an angular torque wrench to properly secure it. You will need a digital wrench here, as you will not have enough room to get in to the aft bolts with a angular dial.

This job on this particular model is not for the faint at heart. It is labor intensive and time consuming..and requires a bit more than basic tools and skills. I'm gathering from the questions you asked (ie removing the spark plugs) your aren't equipped for this.

My friendly, humble advice (from someone who tried and failed here) is to find a local BMW Indy shop and just pay then to do it. My local shop quoted $400 including parts....WELL worth it.

Hey no worries and thanks to all who are expressing caution here. I haven't decided on DIY yet and am still doing some investigating. I've heard plenty of stories about the breather hose. if I decide to go forward with DIY I will likely go after the breather hose first so I don't waste time on other things before breaking that thing.....

So far, best I can tell, no broken bolts. I'm wondering if the broken bolt scenario is more common with '06 and the aluminum bolts ?

So, I took my engine cover off this afternoon to try and sop-up the oil around the plug, with a straw packed with a piece of towel (per a reply to snyperx's thread yesterday).

What I notice now is a fairly prominent pool of oil directly below the valvetronic. See pic. So, I'm thinking about changing that gasket instead of the valve cover. Thinking it will be easier than the vcg.

Also remember that you need to replace the bolts when you take them off! theyre labeled blue for Aluminum.

I don't think they are aluminum on the '07. I ordered some from Tischer, just to have them on hand and they are not labeled blue. I could be wrong but I think the aluminum bolts go with the metal vcg on the '06 325i.

Indy who gave me a quote did not plan on providing new bolts unless they are broken.

Just had a quick look on RealOEM, these bolts don't seem to be the "use only once" type, so provided they are fine should be safe to re-use, and they are not cylinder head stretch bolts that get torqued up...

from the looks of your first picture it seems to be the valvetronic gasket. very inexpensive part and will take at the most 30 min to replace

thanks. I've cleaned up the area and I'm waiting to see if / how oil travels in the future (still no noticeable change in oil level per the computer). If oil continues to build in that area, I may try your suggestion. Seems easier than doing the vcg, maybe worth the gamble on the part and time involved.